curl --request GET \
  --url https://app.manuscritten.com/api/public/signatures \
  --header 'X-API-KEY: <api-key>'

{
  "data": [
    {
      "id": "d32e8929-292a-4ed7-baf1-1e8f74b77542",
      "name": "Firma Javier M."
    }
  ]
}